Antenna assemblies for medical applications

Abstract

A device for directing energy to a target volume of tissue includes a monopole antenna assembly that includes a monopole antenna radiating section having a monopole antenna element surrounded by a dielectric material. The monopole antenna assembly also includes a ground plane disposed at a proximal end of the monopole antenna radiating section, wherein the ground plane is configured to direct energy into the target volume of tissue.

What is claimed is: 
     
       1. A helical antenna assembly for directing energy to a target volume of tissue, comprising:
 a helical antenna element; 
 an outer shell coaxially disposed about the helical antenna element; 
 a tip portion located at a distal end of the helical antenna element; and 
 a conducting ground plane configured to direct energy into the target volume of tissue, wherein the helical antenna element extends outwardly from the conducting ground plane. 
 
     
     
       2. The helical antenna assembly of  claim 1 , further comprising a sleeve member coaxially disposed about the helical antenna element. 
     
     
       3. The helical antenna assembly of  claim 2 , wherein the sleeve member is formed of a dielectric material. 
     
     
       4. The helical antenna assembly of  claim 2 , wherein the sleeve member is formed of an inflatable element, a shape-memory alloy element, or a magneto-electrical actuated element. 
     
     
       5. The helical antenna assembly of  claim 2 , wherein the outer shell is configured to slideably move about the sleeve member in coaxial relation therewith. 
     
     
       6. The helical antenna assembly of  claim 1 , wherein the helical antenna element is formed of a shape-memory material. 
     
     
       7. The helical antenna assembly of  claim 6 , wherein the shape memory material is copper-zinc-aluminum-nickel, copper-aluminum-nickel, or nickel-titanium. 
     
     
       8. The helical antenna assembly of  claim 1 , wherein the outer shell is formed of a conductive material. 
     
     
       9. The helical antenna assembly of  claim 1 , further comprising a dielectric material disposed in an interior area defined by the helical antenna element. 
     
     
       10. The helical antenna assembly of  claim 1 , further comprising an inner shell disposed within the outer shell and about the helical antenna element, the inner shell extending an entire length of the helical antenna element. 
     
     
       11. The helical antenna assembly of  claim 10 , further comprising two longitudinally formed partitions that form a first channel and a second channel in a space between the outer shell and the inner shell. 
     
     
       12. The helical antenna assembly of  claim 1 , further comprising:
 a housing portion; and 
 at least one further helical antenna element, wherein the helical antenna element and the at least one further helical antenna element are coupled to the housing portion and extend longitudinally from a distal end of the housing portion.